This invention relates generally to gas turbine engines, more particularly to combustors used with gas turbine engines.
Known turbine engines include a compressor for compressing air which is suitably mixed with a fuel and channeled to a combustor wherein the mixture is ignited for generating hot combustion gases. The gases are channeled to at least one turbine, which extracts energy from the combustion gases for powering the compressor, as well as for producing useful work, such as propelling a vehicle.
To support engine casings and components within harsh engine environments, at least some known casings and components are supported by a plurality of support rings that are coupled together to form a backbone frame. The backbone frame provides structural support for components that are positioned radially inwardly from the backbone and also provides a means for an engine casing to be coupled around the engine. In addition, because the backbone frame facilitates controlling engine clearance closures defined between the engine casing and components positioned radially inwardly from the backbone frame, such backbone frames are typically designed to be as stiff as possible. At least some known backbone frames used with recuperated engines, include a plurality of beams that extend between forward and aft flanges.
Because of exposure to high temperatures generated within the combustor, fuel injectors used with such engines require cooling. Accordingly, at least some known fuel injectors are cooled by fuel flowing through the fuel injector, as well as through the use of passive “dead air” insulation areas defined internally within the fuel injector. Moreover, to facilitate efficient operation of the fuel injectors, at least some known fuel injectors are designed to enable residual fuel to be forced out of the fuel injector and into an overboard drain during pre-determined combustor operations. In addition, an overall size of the fuel injectors is limited by combustor space limitations. Accordingly, designing an efficient fuel injector for use with such engines may be difficult.